Abstract
A 10-year-old girl visited our hospital with lower abdominal pain. Abdominal computed tomography showed a 10-cm long retroperitoneal mass with homogeneous low density and acute appendicitis. Magnetic resonance imaging revealed that this mass was consistent with lipoma. Conservative management for acute appendicitis was successful ; however, the patient had recurrence of appendicitis after 6 months. Scheduled surgery for resection of the tumor and appendix was performed 3 months after a second trial of conservative management. The tumor was located in the right retroperitoneal space and compressed the ileocecum toward the midline. Mild adhesion to the capsule of the right kidney suggested that the tumor involved perirenal tissues. Histopathology confirmed a lipoma with mature fat cells and chronic appendicitis with fibrosis. There are no pediatric reports of retroperitoneal lipoma with appendicitis. We considered the possibility that ileocecal compression from lipoma caused obstruction of the appendiceal lumen.
